Technical Field
The present disclosure relates to a medical stopcock, which is connected to various medical instruments, infusion containers or the like, and which is capable of switching flow paths arbitrarily.
Background Art
Conventionally, upon performing fluid infusion, blood transfusion, hemodialysis or the like, a liquid is infused into the body by using a medical tube. In order to change flow paths for injecting a medical solution or to mix a plurality of medical solutions and inject the mixed medical solution, a medical stopcock is used.
Conventional medical stopcocks of this type include a medical stopcock described in Japanese Patent Application Publication 2003-159336, for example. The medical stopcock disclosed in Japanese Patent Application Publication 2003-159336 includes a cylindrical body and a stopper. The cylindrical body has a plurality of branches, which are an upstream port section, a downstream port section, and a port section for a side tube. The stopper has a columnar-shaped cock rotatably fitted in the cylindrical body. The stopper is formed with a flow path switching groove including a plurality of longitudinal grooves and is an arc-shaped groove. The stopper having a cock is rotated so as to switch flow paths of liquid passing through the cylindrical body.
A connector is generally attached to the opening of a port section for a side tube to liquid-tightly connect a male connector of a syringe, a lure taper member or the like. The connector includes a valve formed with a slit and a holding member for holding the valve. Through the connector, a medical solution for mixture is injected to the port section for a side tube. In a state where a male connector of a syringe, a lure taper member or the like is not connected to the connector, the port section for a side tube is closed by the valve.
However, in the technique disclosed in Japanese Patent Application Publication 2003-159336, the arc-shaped groove is formed continuously from the upstream port section to the downstream port section. Thus, when all of the ports communicate with each other, a medical solution flowing in from the upstream port section does not flow to the port section for a side tube but flows to the downstream port section. Therefore, when the valve attached to the port section for a side tube is closed, a flow of a medical solution is hardly generated in the port section for a side tube.
As a result, according to the technique described in Japanese Patent Application Publication 2003-159336, a medical solution injected from the port section for a side tube disadvantageously stays in the internal space of the port section for a side tube or in a space formed between the connector and the port section for a side tube when the valve is closed.
In addition, from the port section for a side tube, vasopressor solution and depressor solution, which vary blood pressure, may be injected as medical solutions. When depressor solution is injected from the port section for a side tube in a state where vasopressor solution stays in the port section for a side tube, the staying vasopressor solution may be pushed by depressor solution, causing an inconvenience.